i have 1 child support order, about to get a second one against me, can i get the first one lowered once second one filled

I would strongly recommend that you do the opposite. The amount of the child support for your second child's mother should be adjusted downward, when the Order is entered, based on your child support which you pay to your ex-wife.   Ideally, you should have a very experienced New Jersey child support law firm representing you.  It would be well worth the investment. However, if you choose not to do that, please make sure that you advise the Court about the first child support Order and provide the Court with evidence of that Order.  I have more than 30 years of legal experience and head SALVAGGIO LAW GROUP LLC, a law firm which devotes its entire practice to New Jersey Divorce and Family Law matters.  My firm’s toll-free telephone number is listed below.  Please also feel free to take a look at our Firm Website (www.nj-divorce.net).  I wish you the best. David F. Salvaggio, Esq. (877-355-5281)